Growth in Small-for-Gestational-Age Preterm-Born Children from 0 to 4 Years: The Role of both Prematurity and SGA Status

Abstract

Background: Fullterm small-for-gestational-age children (SGAs) are known for their ability to catch up on growth. Nevertheless, increased risk of growth restriction remains. Evidence on preterm SGA children's growth is lacking. Objective: To determine absolute gains in height and weight, relative growth, and growth restriction in preterm SGAs from 0 to 4 years and how prematurity and SGA status affect these measures. Design/Methods: Community-based cohort study, n = 1,648 preterm-born (gestational age <36 weeks, 57 SGA) and 605 term-born (12 SGA). We defined SGA as a birth weight less than -2 SD (P 2.3) compared to counterparts matched for gestational age. Height, weight, and head circumference were obtained from medical records and translated to z-scores. We defined growth restriction as height or weight less than -2 SD compared to fullterm appropriate-for-gestational-age children (AGAs). Results: Absolute height and weight gains were similar, but the relative growth of preterms and fullterms differed. Preterm AGAs and fullterm SGAs, although not reaching it, caught up towards the fullterm AGA median (z-scores at 4 years: -0.3 to -1.0). By contrast, preterm SGA children's z-scores were still -1.4 to -1.7. Head circumference growth was less affected by prematurity and SGA birth (z-scores at 1 year: 0.1 to -0.7). Catch-up growth mainly took place during infancy. 30-39% of all preterm SGAs showed growth restriction at 4 years. Conclusions: Growth in preterm SGAs is affected considerably by the joint effects of preterm birth and SGA status, resulting in a high proportion of growth restriction.

Marginally low birthweight increases the risk of underweight and short stature at three and a half years of age

“…With regard to term and SGA children, this observation was in concordance with previous studies, suggesting that about 9-11% of growth restrictions persisted in childhood (3,4,6). With regard to term and SGA children, this observation was in concordance with previous studies, suggesting that about 9-11% of growth restrictions persisted in childhood (3,4,6).…”

“…It is related to reduced risk of prolonged growth restriction (3)(4)(5)(6) and to improved neurodevelop-ment (7,8). However, different combinations and degrees of both preterm birth and SGA exist, making the group heterogenic.…”

In utero Programming of Allergic Susceptibility

“…table 1). In addition, animal studies of in utero programming of allergy are needed to remove confounding between the frequent comorbidity of IUGR and prematurity [127,128] and more closely examine the underlying mechanisms of fetal programming of immune function. An additional potential confounder in human studies is that postnatal exposures to allergens vary; animal studies permit control of this variable.…”

Symmetrical and Asymmetrical Growth Restriction in Preterm-Born Children

“…For more detailed information on sampling and procedures, we refer readers to our previous publications. 5,7,14,15,16,17 Statistical Analysis…”

“…4,5 Nevertheless, in 10% of full-term (FT) children and in up to 40% of preterm (PT) children, this catchup is insufficient. 6,7 Regarding head circumference (HC), SGA children, despite some catchup, also persist in having smaller heads compared with children born appropriate for gestational age.…”